Thanks Dave.
I will give that a try.
I just don't understand why I could continue to have a hot bed of embers yet the burning/smoking stops. I'm hoping you're right and it's just a thermal mass issue, but I'm also afraid that it's not getting enough oxygen even though I'm positioning it right next to the side vent.
Plus when it does smoke, I'm losing a lot out of my side vents and it's not rising into the meat chamber. I'm about out of ideas and would really like to avoid setting up a small fan by the side vent to provide oxygen. I'm really hoping it doesn't come to that.
i'll report back. Thanks for the response.